Question

         TIM SO NGUYEN x , BIET :

a) 3636 : ( 12x - 91) = 36                         b) ( x : 23 + 45 ) . 67 = 8911

c) ( 19x + 2.5² ) : 14 = ( 13 - 8 ) ² - 4                d) -12 . ( x- 5 ) + 7(3 -x ) = 5

Answer 1

a. 3636 : (12x - 91) = 36

=> 12x - 91 = 3636 : 36

=> 12x - 91 = 101

=> 12x = 101 + 91

=> 12x = 192

=> x = 192 : 12

=> x = 16

b. (x : 23 + 45). 67 = 8911

=> x : 23 + 45 = 8911 : 67

=> x : 23 + 45 = 133

=> x : 23 = 133 - 45

=> x : 23 = 88

=> x = 88 . 23

=> x = 2024

c. (19x + 2.5²) : 14 = (13 - 8)² - 4

=> (19x + 2.25) : 14 = 5² - 4

=> (19x + 50) : 14 = 25 - 4

=> (19x + 50) : 14 = 21

=> 19x + 50 = 21. 14

=> 19x + 50 = 294

=> 19x = 294 - 50

=> 19x = 244

=> x = 244 : 19

=> x = 244/19 (Xem lại đề)

d. -12 .(x - 5) + 7.(3 - x) = 5

=> -12x + 60 + 21 - 7x = 5

=> -19x + 81 = 5

=> -19x = 5 - 81

=> -19x = -76

=> x = -76 : (-19)

=> x = 4

Answer 2

3636:(12.x-76):4=36

Các bạn giúp với